This invention is to undo a tubular knitted fabric which is knitted in tubular form by a circular knitting machine, and more particularly to a device for undoing or unknitting yarn from a tubular knitted fabric by rewinding a yarn to be unknitted from the knitted goods on a bobbin without causing the twisting and the like.
Heretofore, the knitted goods are such which are knitted by means of a flat knitting type machine or which are knitted by a circular knitting type machine. These knitted goods generally use expensive yarns and should an error occur in the knitting, the yarn is unknitted and is rewound on a bobbin to be reused.
As a device for rewinding the yarn on the bobbin while undoing the foregoing knitted goods, Japanese Patent Application No. 1-303262 was filed in Japan by an applicant identical with the present applicant of this application. Namely, the device of this application, as shown in FIG. 6, a yarn guide shaft 102 and a detecting bar 103 for detecting a hooking of the yarn are installed at positions that become a series for each of a plurality of yarn winding rotary members 101, and a guide lateral lever 104 is installed at a predetermined interval from the detecting bar 103, and a plurality of yarns 106 undone from a knitted fabric 105 are wound on a bobbin 108 provided on each yarn winding rotary member 101 through a yarn guide 107 of each detecting bar 103 from the above of the guide lateral lever 104, and in the condition where the detecting bar 103 is descended from the foregoing position by its own dead weight, the yarn 106 is introduced and guided in an inverted triangle form between the yarn guide 109 of the guide shaft 102 and the guide lateral lever 104, and when the hooking occurs at a stitch of the knitted fabric 105 which results in the condition where the yarn is not undone, the detecting bar 103 is lifted between the guide shaft 102 and the guide lateral lever 104 by the tension of the yarn and the drive device for the yarn winding rotary member 101 is initiated by the elevation of the detecting bar 103, and the vibration is applied to the stitch of the knitted fabric 105 to unknit the hooking of the stitch.
However, the foregoing device for undoing yarn from the knitted goods described in the foregoing was suitable for undoing the knitted fabric knitted by a flat knitting machine, but it was not suitable for undoing the tubular knitted fabric produced by the circular knitting machine. Namely, the flat knitting machine reciprocated the yarn guide to knit so that the knitted fabric was finished in a flat form and, in order to undo it, the yarn was undone while it was reciprocating the stitch of the knitted fabric. But, the hooking tended to occur at both end portions of the knitted fabric so that when the hooking occurred, the detecting bar lifted to stop the rotation of the yarn winding rotary member temporarily to eliminate the hooking of the yarn by giving the vibration to the stitch. However, the circular knitting machine was to knit while the yarn guide was rotating so that the knitted goods was knitted in tubular form and in order to undo it, the unknitting stitch of the yarn was taken place like rounding around the knitted fabric, and for this reason, in the conventional yarn unknitting device for the tubular knitted fabric, the twisting of the yarn and the like occurred at the time of the unknitting which was the problem